Leica M Series Factory Tips

Factory tips on the

M-Series Leicas

The M-series Leica is still the
standard of excellence among
rangefinder-type 35mm cameras. Yet
despite Leica's popularity and length
of time in service, there seems to be a
long-felt vacuum of factory
information in the repair field — at
least, so it appears from the
individual questions we've been
answering at National Camera.

So instructor Monty Witt ventured
forth to Leitz in hopes of obtaining
some first-hand factory servicing tips.
The notes he brought back from New
Jersey should be of prime interest to
CRAFTSMAN readers. And we'd like
to express our gratitude to Leitz for
their courtesy and assistance in
gathering this material.

Although Monty also received

bench training on the Leicaflex and
the Leica M5, we'll confine ourselves
this time to the notes he kept on the
M2, M3, and M4 ( mainly because of
the immediate availability of an M2
which was used for most of the

illustrations). We plan to pass along
the Leicaflex and M5 information in
future CRAFTSMAN articles.

In addition to Monty's notes, we'll
include some basic information on the
M-series Leicas. If you're already a
proficient Leica technician, please
stick with us — you should find

something new and useful besides
what may already be familiar.

Disassembly Steps For The

M-Series Leicas

The Leica M2 illustrated in Fig. 1 is
a slightly simplified version of the
original M-series Leica, the M3. The
M3 set the design precedents for the

other M-series Leicas: the Ml

(further simplified from the M2) and

the MP (a special model for press
photographers quite similar to the
M2). More recently, the M4 (an
improved version of the M3) took over
the top roost. But all the Leica models
mentioned are nearly identical from
the technician's viewpoint. Only the
M5, which we'll not discuss here,
represents a radical departure from

the original design.

If you've been in the repair business

for any length of time, you can no
doubt take a Leica apart. But we find
that most technicians spend time

removing parts that could just as well

be left in place. So we'll outline the
disassembly techniques to reach the
adjustments and timing points of
concern.

Starting with the top cover plate

disassembly, remove the screw at the

top of the lens mounting ring, Fig. 1.

This screw is normally sealed with a
black locking agent. Since the screw
must be removed to pull either the top

cover plate or the body shell, you can
frequently tell from the condition of
the locking agent whether or not the
camera has previously been
disassembled.

Next, remove the camera's base
plate as you would for loading film.
The Leicas based on the M3 design
carry over the load-from-the-bottom
technique of the screw-mount Leicas.
But the M-series Leicas added a
hinged back to facilitate loading. You
can remove the hinged back by
pushing the release pin from left to
right in Fig. 2.

Reaching into the supply-spool
cavity, wedge the rewind fork to
prevent it from turning. Then, use a
Multispan wrench to unscrew the

cover screw that holds the rewind
knob, Fig. 3. An exception here is the
M4—the rewind knob in the M4 sits at
a convenient cant and is held by a
setscrew.

Probably one of the main
disassembly problems faced by the
technician is the removal of the wind
lever cover screw, Fig. 3. The wind
lever cover screw has a right-hand
thread, but it may be extremely tight.
To avoid scarring the polished

RANGEFINDER WINDOW

REWIND LEVER

Figure 1

COVER SCREW FOR
VERTICAL RANGEFINDER
ADJUSTMENT

FRAME LINE

MASK WINDOW

FRAME LINE SELECTOR LEVER

VIEWFINDER WINDOW

RELEASE PIN

Figure 2

surface, use a Flexiclamp wrench or a
split collet to unscrew the wind lever

cover screw. You can then lift off the

wind lever and, in the M2, the counter
dial.

Also, if you're working on the M2,

remove the cover plate retaining
screw shown in Fig. 3. You won't find
this retaining screw in the M3 or the
M4 — instead, unscrew the retaining

ring accessible after removing the
wind lever. The reason for the
difference is that the AA2 has an
external, manually set counter dial.

But in the M3 and AA4, the counter dial

is underneath the top cover plate. The
spring-loaded counter dial in the M3
and AA4 automatically returns when
you pull out the film take-up spool.

Another tricky part to remove is the

retaining ring around the rewind
shaft. The problem here is that
standard tools can't do the job — there

isn't enough room for a Flexiclamp
wrench and there are no notches for a
Multispan wrench. So here's one place
that you may wish to design a special,
tubular tool that fits over the retaining

ring.

The remaining top cover plate
components are no problem. Take out
the speed knob retaining screw, Fig.
3, and lift off the speed knob. And
remove the four screws holding the

accessory shoe, also shown in Fig. 3.

Lift off the accessory shoe, the

accessory shoe pressure plate, and
the spring.

Proceeding to the back of the

camera, unscrew the two flash socket
cover rings and the two flash socket

bushings. If you're working on the M3,

also unscrew the eyepiece frame.
Now, lift off the top cover plate.

Before we go into the adjustments

and timing points now visible, we'll
complete the disassembly of the body
shell and the rangefinder, Fig. 4. You

may, however, wish to replace the
wind lever with its cover screw to
examine the operation at the top of the

camera. Then, turn over the camera

and remove the three screws holding
the bottom cover plate, Fig. 5. Lift off
the bottom cover plate and the base

lock plate.

REWIND

KNOB
COVER
SCREW

ACCESSORY SHOE SCREWS

Figure 3

RANGEFINDER

ASSEMBLY

Figure 4

BOTTOM COVER PLATE RETAINING SCREWS

Figure 5

PIVOT PLATE
FOR CURTAIN

END OF OPENING
CURTAIN LATCH

WIND GEAR

AND OPENING

CURTAIN LATCH

COUNTER DIAL

SPEED KNOB

RETAINING SCREW

SPEED SELECTOR

SAFETY SWITCH FOR "FP" SYNC CONTACTS

"X"-SYNC ADJUSTMENT

DRUM BEARING PLATE

WIND LEVER

COVER SCREW

WIND CAM

BASE LOCK PLATE

CLOSING CURTAIN

TAKE-UP ROLLER

COVER

PLATE

RETAINING

SCREW

LOCKING

COLLARS

Adjustments At The Bottom Of
The M-Series Leica

Several adjustment points are now
visible at the bottom of the camera,
Fig. 6. Notice that the M-series Leicas
departed from the conventional
methods of locking the curtain take-up
rollers. To adjust the curtain tensions,

FLAT
RELEASE
SPRING

Figure 6

SETSCREW

ADJUSTMENT

CLOSING CURTAIN
BRAKE ADJUSTMENT

OPENING CURTAIN

TAKE-UP ROLLER

use a screwdriver with a blade
slightly wider than the slotted ends of

the take-up rollers central shafts.

Insert the screwdriver into the slotted
end of one central shaft and push
down — that depresses the locking
collar and frees the central shaft. You
can now turn the screwdriver to add
or let off tension.

Another departure from tradition is
the elimination of the interlocking­stud arrangement common to the
drum-type focal-plane shutters. In the
shutter-cocked position, a slot in the
curtain wind gear clears the drum
gear at the bottom of the curtain
drum. Then, the opening curtain
latch, Fig. 6, drops into engagement

with the opening curtain cam
underneath the drum gear.

Depressing the release button

pushes the end of the flat release
spring against the opening curtain
latch. So the opening curtain latch,
pushed out of engagement with the
opening curtain cam, frees the
opening curtain. Simultaneously, the
flat release spring allows the closing
curtain latch, Fig. 7, to drop down and
engage the closing curtain cam.

meeting these specifications is the
setscrew on the flat release spring,
Fig. 6.

The "X"-sync adjustment is
another conveniently located
adjustment point visible in Fig. 6. The
collar with the Multispan notches
controls an eccentrically positioned
stud at the other side of the bottom
plate. And the stud, in turn, controls
the position of the fixed "X" contact.
Turning the collar corrects the "X"­sync delay by setting the proper space
gap between the two contacts.

A second eccentric controls the
tension of the closing curtain brake
spring, Fig. 6. The brake spring,
which we'll see after removing the
body shell, engages a cam operated
by the closing curtain drum. And by
turning the eccentric from the bottom
of the camera, you can control the
amount of braking action.

Check the proper tension for the
closing curtain brake by first setting
the shutter to "bulb." Then, cock and

release the shutter. The closing

curtain should be stopped by the

brake spring before reaching the
extreme limit of its travel. So try

pulling the closing curtain in the
direction of its release movement —
you should be able to pull the curtain

an additional 0.1mm—0.5mm.

In some cameras, there's also an
eccentric adjustment for the opening
curtain brake; the opening curtain
brake eccentric is shown from a Leica
M3 in Fig. 8. Check the adjustment of
the opening curtain brake by holding

the shutter open at the "bulb" setting.
Now, looking from the front of the
focal-plane aperture, examine the
position of the opening curtain bar at
the right-hand side of the camera. If
the opening curtain brake is properly
adjusted, the edge of the opening
curtain bar should be 1.5mm —

2.5mm beyond the edge of the focal­plane aperture.

Before moving too far away from

Fig. 6, we should point out the bayonet

cap in the focal-plane light shield. You
can remove the bayonet cap after

rotating it a partial turn. As you will

see a little later, removing the
bayonet cap uncovers an access hole
in the focal-plane light shield — a hole
which makes it easier to reach one of
the rangefinder retaining screws.

RELEASE BUTTON

CLOSING CURTAIN

RELEASE

ROD

FLAT

RELEASE

SPRING

OPENING CURTAIN

LATCH

RELEASE CYCLE

Figure 7 '

LATCH

DRUM GEAR

Leica's specifications here are that
the opening curtain should release
when you depress the release button

approximately 1.5mm. Once you let
up on the release button, the flat
release spring raises the closing
curtain latch above the closing curtain
cam. Checking the operation at
"bulb," the release button should

have an additional 0.2mm upward

travel after the closing curtain has

released. The adjustment point for

Figure 8

REWIND

LEVER
SCREW

Figure 9 •

LEICA M3 OPENING CURTAIN BRAKE ADJUSTMENT

BODY SHELL

SCREWS

RANGEFINDER CONTROL ARM